Chōryaku (長暦) was a Japanese era (年号, nengō, lit.
"year name") after Chōgen and before Chōkyū.
This period spanned the years from April 1037[1] through 1040.
[2] The reigning emperor was Go-Suzaku-tennō (後朱雀天皇).
This article about a Japanese era name is a stub.